title: A study of the interaction between enantiomers of zolmitriptan and hydroxypropyl-beta-cyclodextrin by capillary electrophoresis.
abstract: The enantioresolution of zolmitriptan was performed using cyclodextrin (CD)-modified capillary zone electrophoresis (CZE) with hydroxypropyl-beta-CD (HP-beta-CD) as the chiral selector. The influence of experimental conditions on the enantioseparation of zolmitriptan, such as pH, temperature, applied voltage, and concentrations of running electrolyte and CD, was systematically investigated, obtaining a baseline separation of two enantiomers by the use of a 25 mM sodium dihydrogen phosphate (SDPH) running electrolyte (pH 2.4) containing 30 mM HP-beta-CD at 15 degrees C. Binding constants for each enantiomer-HP-beta-CD pair at different temperatures, as well as thermodynamic parameters for binding, were calculated. A nonlinear van't Hoff plot was obtained, indicating that the thermodynamic parameters of complexation were temperature-dependent for zolmitriptan enantiomers. The significant contribution of the enthalpy difference to the Gibbs free energy change suggested a stereomeric barrier mechanism for chiral recognition.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of the Ministry of Education, Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, China.
authors.forename: Nannan
authors.initials: N
authors.lastname: Pang
authors.forename: Zhengxiang
authors.initials: Z
authors.lastname: Zhang
authors.forename: Yu
authors.initials: Y
authors.lastname: Bai
authors.forename: Huwei
authors.initials: H
authors.lastname: Liu
mesh_terms: D000073738:2-Hydroxypropyl-beta-cyclodextrin; D004563:Electrochemistry; D004573:Electrolytes / Q000737:chemistry; D019075:Electrophoresis, Capillary; D006863:Hydrogen-Ion Concentration; D008968:Molecular Conformation; D023303:Oxazolidinones / Q000032:analysis* / Q000737:chemistry*; D010756:Phosphoric Acids / Q000737:chemistry; D013237:Stereoisomerism; D013696:Temperature; D013816:Thermodynamics; D014363:Tryptamines / Q000032:analysis* / Q000737:chemistry*; D047392:beta-Cyclodextrins / Q000032:analysis* / Q000737:chemistry*
chemical_list: D004573:Electrolytes; D023303:Oxazolidinones; D010756:Phosphoric Acids; D014363:Tryptamines; D047392:beta-Cyclodextrins; D000073738:2-Hydroxypropyl-beta-cyclodextrin; C089750:zolmitriptan; C030242:phosphoric acid